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Author Gehrke, K.; Moshnyaga, V.; Samwer, K.; Lebedev, O.I.; Verbeeck, J.; Kirilenko, D.; Van Tendeloo, G. url  doi
openurl 
  Title Interface controlled electronic variations in correlated heterostructures Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 82 Issue 11 Pages 113101,1-113101,4  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract An interface modification of (LaCa)MnO3-BaTiO3 superlattices was found to massively influence magnetic and magnetotransport properties. Moreover it determines the crystal structure of the manganite layers, changing it from orthorhombic (Pnma) for the conventional superlattice (cSL), to rhombohedral (R3̅ c) for the modified one (mSL). While the cSL shows extremely nonlinear ac transport, the mSL is an electrically homogeneous material. The observations go beyond an oversimplified picture of dead interface layers and evidence the importance of electronic correlations at perovskite interfaces.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000281643200001 Publication Date 2010-09-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 9 Open Access  
  Notes This work was supported by DFG via SFB 602, TPA2. Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:84249UA @ admin @ c:irua:84249 Serial 1691  
Permanent link to this record
 

 
Author van den Heuvel, W.; Tikhomirov, V.K.; Kirilenko, D.; Schildermans, N.; Chibotaru, L.F.; Vanacken, J.; Gredin, P.; Mortier, M.; Van Tendeloo, G.; Moshchalkov, V.V. url  doi
openurl 
  Title Ultralow blocking temperature and breakdown of the giant spin model in Er3+-doped nanoparticles Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 82 Issue 9 Pages 094421-094421,8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The magnetization of luminescent Er3+-doped PbF2 nanoparticles (formula Er0.3Pb0.7F2.3) has been studied. Despite the high concentration of the doping Er3+ ions and relatively large size (8 nm) of these nanoparticles we have found no deviation between field-cooled and zero-field-cooled magnetization curves down to T=0.35 K, which points out an ultralow blocking temperature for the reversal of magnetization. We also have found strongly deviating magnetization curves M(H/T) for different temperatures T. These results altogether show that the investigated nanoparticles are not superparamagnetic, but rather each Er3+ ion in these nanoparticles is found in a paramagnetic state down to very low temperatures, which implies the breakdown of the Néel-Brown giant spin model in the case of these nanoparticles. Calculations of magnetization within a paramagnetic model of noninteracting Er3+ ions completely support this conclusion. Due to the ultralow blocking temperature, these nanoparticles have a potential for magnetic field-induced nanoscale refrigeration with an option of their optical localization and temperature control.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000281773300005 Publication Date 2010-09-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 11 Open Access  
  Notes Fwo Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:85423 Serial 3796  
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Author Tsirlin, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Rosner, H. url  doi
openurl 
  Title Interplay of atomic displacement in the quantum magnet (CuCI)LaNb2O7 Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 82 Issue 5 Pages 054107,1-054107,12  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000280849400001 Publication Date 2010-08-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 13 Open Access  
  Notes Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:83991 Serial 1706  
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Author Maignan, A.; Lebedev, O.I.; Van Tendeloo, G.; Martin, C.; Hebert, S. url  doi
openurl 
  Title Metal to insulator transition in the n-type hollandite vanadate Pb1.6V8O16 Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 82 Issue 3 Pages 035122, 1-035122,5  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The transport and magnetic measurements of polycrystalline Pb1.6V8O16 hollandite reveal a concomitant metal to insulator and antiferromagnetic transition at TMI≈140 K. A clear localization is found below TMI, evidenced by a rapid increase in the absolute value of the negative Seebeck coefficient. The structural study by x-ray and transmission electron microscopy confirms the hollandite structure and shows that no structural transition occurs at TMI, ruling out a possible charge orbital ordering. The negative Seebeck coefficient observed from 50 K up to 900 K, with values reaching S=−38 μV K−1 at 900 K, is explained by the electron doping of ∼1.4e− in the V empty t2g orbitals responsible for the bad metal resistivity (ρ900 K∼2 mΩ cm). As this S value is close to that obtained by considering only the spin and orbital degeneracies, it is expected that |S| for such vanadates will not be sensitive at high temperature to the t2g band filling  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000280366300002 Publication Date 2010-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 10 Open Access  
  Notes Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:84065 Serial 2009  
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Author Tsirlin, A.A.; Nath, R.; Abakumov, A.M.; Shpanchenko, R.V.; Geibel, C.; Rosner, H. url  doi
openurl 
  Title Frustrated square lattice with spatial anisotropy: crystal structure and magnetic properties of PbZnVO(PO4)2 Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 17 Pages 174424,1-174424,13  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Crystal structure and magnetic properties of the layered vanadium phosphate PbZnVO(PO4)2 are studied using x-ray powder diffraction, magnetization and specific-heat measurements, as well as band-structure calculations. The compound resembles AA′VO(PO4)2 vanadium phosphates and fits to the extended frustrated square-lattice model with the couplings J1, J1′ between nearest neighbors and J2, J2′ between next-nearest neighbors. The temperature dependence of the magnetization yields estimates of averaged nearest-neighbor and next-nearest-neighbor couplings, J̅ 1≃−5.2 K and J̅ 2≃10.0 K, respectively. The effective frustration ratio α=J̅ 2/J̅ 1 amounts to −1.9 and suggests columnar antiferromagnetic ordering in PbZnVO(PO4)2. Specific-heat data support the estimates of J̅ 1 and J̅ 2 and indicate a likely magnetic ordering transition at 3.9 K. However, the averaged couplings underestimate the saturation field, thus pointing to the spatial anisotropy of the nearest-neighbor interactions. Band-structure calculations confirm the identification of ferromagnetic J1, J1′ and antiferromagnetic J2, J2′ in PbZnVO(PO4)2 and yield (J1′−J1)≃1.1 K in excellent agreement with the experimental value of 1.1 K, deduced from the difference between the expected and experimentally measured saturation fields. Based on the comparison of layered vanadium phosphates with different metal cations, we show that a moderate spatial anisotropy of the frustrated square lattice has minor influence on the thermodynamic properties of the model. We discuss relevant geometrical parameters, controlling the exchange interactions in these compounds and propose a strategy for further design of strongly frustrated square-lattice materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000278141600082 Publication Date 2010-05-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 27 Open Access  
  Notes Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:83384 Serial 1294  
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Author Jorissen, K.; Rehr, J.J.; Verbeeck, J. url  doi
openurl 
  Title Multiple scattering calculations of relativistic electron energy loss spectra Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 15 Pages 155108,1-155108,6  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract A generalization of the real-space Greens-function approach is presented for ab initio calculations of relativistic electron energy loss spectra (EELS) which are particularly important in anisotropic materials. The approach incorporates relativistic effects in terms of the transition tensor within the dipole-selection rule. In particular, the method accounts for relativistic corrections to the magic angle in orientation resolved EELS experiments. The approach is validated by a study of the graphite C  K edge, for which we present an accurate magic angle measurement consistent with the predicted value.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000277210500038 Publication Date 2010-04-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 24 Open Access  
  Notes Fwo; Esteem 026019 Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:82805UA @ admin @ c:irua:82805 Serial 2230  
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Author Xu, T.; Nys, J.-P.; Addad, A.; Lebedev, O.I.; Urbieta, A.; Salhi, B.; Berthe, M.; Grandidier, B.; Stievenard, D. url  doi
openurl 
  Title Faceted sidewalls of silicon nanowires: Au-induced structural reconstructions and electronic properties Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 11 Pages 115403,1-115403,10  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Si nanowires with a ⟨111⟩ orientation, synthesized by vapor-liquid-solid process with low silane partial pressure reactant and gold as the catalyst, are known to exhibit sawtooth facets containing gold adsorbates. We report herein the study of the nanowire morphology by means of transmission electron microscopy and scanning tunneling microscopy. The nanowires consist of faceted sidewalls. The number of the sidewalls changes from 12 to 6 along the growth axis, giving rise to nanowires with an irregular hexagonal cross section at their base. The sidewalls are covered with Au-rich clusters. Their facets also exhibit atomic structures that reveal the presence of gold, resulting from the diffusion of gold during the growth. Based on these observations, the tapering of the nanowire is found to be related to two contributions: the reduction in the catalyst particle size during the growth and lateral overgrowth from the direct incorporation of Si species onto the nanowire sidewalls. Because the rearrangement of atoms at surfaces and interfaces might affect the growth kinetics, the trigonal symmetry as well as the higher lateral growth rate on the widest sidewalls are explained from the existence of an interfacial atomic structure with two inequivalent parts in the unit cell. Finally, spectroscopic measurements were performed on the major facets and revealed a metallic behavior at 77 K.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000276248800116 Publication Date 2010-03-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 42 Open Access  
  Notes Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:82273 Serial 1168  
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Author Verbeeck, J.; Bals, S.; Lamoen, D.; Luysberg, M.; Huijben, M.; Rijnders, G.; Brinkman, A.; Hilgenkamp, H.; Blank, D.H.A.; Van Tendeloo, G. url  doi
openurl 
  Title Electronic reconstruction at n-type SrTiO3/LaAlO3 interfaces Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 8 Pages 085113,1-085113,6  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Electron-energy-loss spectroscopy (EELS) is used to investigate single layers of LaAlO3 grown on SrTiO3 having an n-type interface as well as multilayers of LaAlO3 and SrTiO3 in which both n- and p-type interfaces occur. Only minor changes in Ti valence at the n-type interface are observed. This finding seems to contradict earlier experiments for other SrTiO3/LaAlO3 systems where large deviations in Ti valency were assumed to be responsible for the conductivity of these interfaces. Ab initio calculations have been carried out in order to interpret our EELS results. Using the concept of Bader charges, it is demonstrated that the so-called polar discontinuity is mainly resolved by lattice distortions and to a far lesser extent by changes in valency for both single layer and multilayer geometries.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000275053300040 Publication Date 2010-02-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 25 Open Access  
  Notes Esteem 026019; Fwo Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:81768UA @ admin @ c:irua:81768 Serial 1005  
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Author Nistor, S.V.; Stefan, M.; Nistor, L.C.; Goovaerts, E.; Van Tendeloo, G. url  doi
openurl 
  Title Incorporation and localization of substitutional Mn2+ ions in cubic ZnS quantum dots Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 3 Pages 035336,1-035336,6  
  Keywords A1 Journal article; Nanostructured and organic optical and electronic materials (NANOrOPT); Electron microscopy for materials research (EMAT)  
  Abstract Multifrequency electron paramagnetic resonance (EPR) and high resolution transmission electron microscopy (HRTEM) investigations were performed on small (2 nm) cubic ZnS nanocrystals (quantum dotsQDs) doped with 0.2% mol Mn2+, self-assembled into a mesoporous structure. The EPR data analysis shows that the substitutional Mn2+ ions are localized at Zn2+ sites subjected to a local axial lattice distortion, resulting in the observed zero-field-splitting parameter |D|=41×10−4 cm−1. The local distortion is attributed to the presence in the second shell of ligands of a stacking fault or twin, which alters the normal stacking sequence of the cubic structure. The HRTEM results confirm the presence of such extended planar defects in a large percentage of the investigated QDs, which makes possible the proposed substitutional Mn2+ impurity ions localization model. Based on these results it is suggested that the high doping levels of Mn2+ ions observed in cubic ZnS and possible in other II-VI semiconductor QDs prepared at low temperatures can be explained by the assistance of the extended lattice defects in the impurities incorporation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000277970900007 Publication Date 2010-01-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 55 Open Access  
  Notes Fwo Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:83649 Serial 1597  
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Author Zhang, L.; Turner, S.; Brosens, F.; Verbeeck, J. url  doi
openurl 
  Title Model-based determination of dielectric function by STEM low-loss EELS Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 3 Pages 035102  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Theory of quantum systems and complex systems  
  Abstract Dielectric properties of materials are crucial in describing the electromagnetic response of materials. As devices are becoming considerably smaller than the optical wavelength, the conventional measuring methods based on optical response are limited by their spatial resolution. Electron energy loss spectroscopy performed in a scanning transmission electron microscope is a good alternative to obtain the dielectric properties with excellent spatial resolution. Due to the overlap of diffraction discs in scanning transmission electron microscopy, it is difficult to apply conventional experimental settings to suppress retardation losses. In this contribution, a relativistic dielectric model for the loss function is presented which is used in a model based optimization scheme to estimate the complex dielectric function of a material. The method is applied to experiments on bulk diamond and SrTiO3 and shows a good agreement with optical reference data when retardation effects are included. Application of this technique to nanoparticles is possible but several theoretical assumptions made in the model of the loss function are violated and interpretation becomes problematic.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000274002300027 Publication Date 2010-01-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 9 Open Access  
  Notes Esteem – 026019; Fwo Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:81258UA @ admin @ c:irua:81258 Serial 2098  
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Author Salje, E.K.H.; Zhang, H.; Idrissi, H.; Schryvers, D.; Carpenter, M.A.; Moya, X.; Planes, A. url  doi
openurl 
  Title Mechanical resonance of the austenite/martensite interface and the pinning of the martensitic microstructures by dislocations in Cu74.08Al23.13Be2.79 Type A1 Journal article
  Year 2009 Publication Physical review: B: condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 80 Issue 13 Pages 134114,1-1134114,8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract A single crystal of Cu74.08Al23.13Be2.79 undergoes a martensitic phase transition at 246 and 232 K under heating and cooling, respectively. The phase fronts between the austenite and martensite regions of the sample are weakly mobile with a power-law resonance under external stress fields. Surprisingly, the martensite phase is elastically much harder than the austenite phase showing that interfaces between various crystallographic variants are strongly pinned and cannot be moved by external stress while the phase boundary between the austenite and martensite regions in the sample remains mobile. This unusual behavior was studied by dynamical mechanical analysis (DMA) and resonant ultrasound spectroscopy. The remnant strain, storage modulus, and internal friction were recorded simultaneously for different applied forces in DMA. With increasing forces, the remnant strain increases monotonously while the internal friction peak height shows a minimum at 300 mN. Transmission electron microscopy shows that the pinning is generated by dislocations which are inherited from the austenite phase.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000271351300033 Publication Date 2009-10-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 38 Open Access  
  Notes Multimat Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:78542 Serial 1975  
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Author di Vece, M.; Bals, S.; Lievens, P.; Van Tendeloo, G. url  doi
openurl 
  Title Compositional changes of Pd-Au bimetallic nanoclusters upon hydrogenation Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 80 Issue 12 Pages 125420,1-125420,4  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Changes in the size distribution and composition of bimetallic Pd-Au nanoclusters have been observed after hydrogen exposure. This effect is caused by hydrogen-induced Ostwald ripening whereby the hydrogen reduces the binding energy of the cluster atoms leading to their detachment from the cluster. The composition changes due to a difference in mobility of the detached palladium and gold atoms on the surface. Fast palladium atoms contribute to the formation of larger nanoclusters, while the slower gold atoms are confined to the smaller nanoclusters. These transformations in the Pd-Au nanocluster size and composition set a limit for chemical reactions in which such nanoclusters are involved together with hydrogen.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000270383300121 Publication Date 2009-09-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 28 Open Access  
  Notes Fwo; Goa; Iap-Vi; Esteem 026019 Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:79232 Serial 445  
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Author Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. url  doi
openurl 
  Title Superconducting nanowires: interplay of discrete transverse modes with supercurrent Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 80 Issue 2 Pages 024513,1-024513,11  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract From a numerical solution of the Bogoliubov-de Gennes equations, we investigate an interplay of the transverse discrete modes with a longitudinal supercurrent in a metallic cylindrical superconducting nanowire. The superconductor-to-normal transition induced by a longitudinal superflow of electrons is found to occur as a cascade of jumps in the order parameter (supercurrent and superfluid density) as a function of the superfluid velocity for diameters d<1015 nm (for Al parameters) and sufficiently low temperatures T<0.30.4Tc, with Tc the critical temperature. When approaching Tc, the jumps are smoothed into steplike but continuous drops. A similar picture occurs for d>1520 nm. Only when the diameter exceeds 5070 nm the quantum-size cascades are fully washed out, and we arrive at the mesoscopic regime. Below this regime the critical current density jc exhibits the quantum-size oscillations with pronounced resonant enhancements: the smaller the diameter, the more significant is the enhancement. Thickness fluctuations of real samples will smooth out such oscillations into an overall growth of jc with decreasing nanowire diameter.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000268617500092 Publication Date 2009-07-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 21 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:77949 Serial 3358  
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Author Resta, V.; Afonso, C.N.; Piscopiello, E.; Van Tendeloo, G. url  doi
openurl 
  Title Role of substrate on nucleation and morphology of gold nanoparticles produced by pulsed laser deposition Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 79 Issue 23 Pages 235409,1-235409,6  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract This work compares the morphology of gold nanoparticles (NPs) produced at room temperature on single-crystalline (MgO nanocubes and plates) and amorphous (carbon/glass plates) substrates by pulsed laser deposition (PLD). The results show that similar deposition and nucleation rates (>5×1013 cm−2 s−1) are achieved irrespective of the nature of the substrate. Instead, the shape of NPs is substrate dependent, i.e., quasispheres and faceted NPs in amorphous and single-crystalline substrates, respectively. The shape of the latter is octahedral for small NPs and truncated octahedral for large ones, with the degree of truncation being well explained using the Wulff-Kaichew theorem. Furthermore, epitaxial growth at room temperature is demonstrated for single-crystalline substrate. The large fraction of ions having energies higher than 200 eV and the large flux of species arriving to the substrate (1016 at. cm−2 s−1) involved in the PLD process are, respectively, found to be responsible for the high nucleation rates and epitaxial growth at room temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000267699500116 Publication Date 2009-06-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 16 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:77692 Serial 2922  
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Author Moshnyaga, V.; Gehrke, K.; Sudheendra, L.; Belenchuk, A.; Raabe, S.; Shapoval, O.; Verbeeck, J.; Van Tendeloo, G.; Samwer, K. url  doi
openurl 
  Title Electrical nonlinearity in colossal magnetoresistance manganite films: relevance of correlated polarons Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 79 Issue 13 Pages 134413,1-134413,8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The metal-insulator (MI) transition in epitaxial thin films of La0.75Ca0.25MnO3 (LCMO) is accompanied by the appearance of an intrinsic electrical nonlinearity. The latter, probed by electrical third harmonic voltage, U3, or resistance, R3=dU3/dJ, is drastically enhanced in the vicinity of the MI transition, TMI=267 K. Applied magnetic field, B=5 T, suppresses the nonlinearity, resulting in a huge nonlinear CMR3(TMI)~105%. R3 shows a peculiar low-frequency (1 kHz) dependence, R3~(-0)n, with exponent, n, changing across the MI transition from n~1,52 for TTMI to n=1 (T<TMI). The observed electrical nonlinearity in LCMO reflects the behavior of correlated polarons, the number of which dramatically enhances in the vicinity of TMI. We argued that correlated polarons, considered as electric-elastic quadrupoles, provide a nonlinear (quadratic) coupling to the electric field, yielding a third harmonic electric nonlinearity in LCMO. The reference film of La0.7Sr0.3MnO3 (LSMO), a prototypic double exchange system with second-order phase transition, is characterized as a linear metallic material in the whole range of temperatures (T=10400 K), magnetic fields (B=05 T), and frequencies (=11000 Hz).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000265942800074 Publication Date 2009-04-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 28 Open Access  
  Notes Esteem 026019 Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:77022UA @ admin @ c:irua:77022 Serial 893  
Permanent link to this record
 

 
Author Werner, R.; Raisch, C.; Leca, V.; Ion, V.; Bals, S.; Van Tendeloo, G.; Chasse, T.; Kleiner, R.; Koelle, D. url  doi
openurl 
  Title Transport, magnetic, and structural properties of La0.7Ce0.3MnO3 thin films: evidence for hole-doping Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 79 Issue 5 Pages 054416,1-054416,8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Cerium-doped manganite thin films were grown epitaxially by pulsed laser deposition at 720 °C and oxygen pressure pO2=125 Pa and were subjected to different annealing steps. According to x-ray diffraction (XRD) data, the formation of CeO2 as a secondary phase could be avoided for pO28 Pa. However, transmission electron microscopy shows the presence of CeO2 nanoclusters even in those films which appear to be single phase in XRD. With O2 annealing, the metal-to-insulator transition temperature increases, while the saturation magnetization decreases and stays well below the theoretical value for electron-doped La0.7Ce0.3MnO3 with mixed Mn3+/Mn2+ valences. The same trend is observed with decreasing film thickness from 100 to 20 nm, indicating a higher oxygen content for thinner films. Hall measurements on a film which shows a metal-to-insulator transition clearly reveal holes as dominating charge carriers. Combining data from x-ray photoemission spectroscopy, for determination of the oxygen content, and x-ray absorption spectroscopy (XAS), for determination of the hole concentration and cation valences, we find that with increasing oxygen content the hole concentration increases and Mn valences are shifted from 2+ to 4+. The dominating Mn valences in the films are Mn3+ and Mn4+, and only a small amount of Mn2+ ions can be observed by XAS. Mn2+ and Ce4+ XAS signals obtained in surface-sensitive total electron yield mode are strongly reduced in the bulk-sensitive fluorescence mode, which indicates hole-doping in the bulk for those films which do show a metal-to-insulator transition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000263815400057 Publication Date 2009-02-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 25 Open Access  
  Notes Esteem 026019; Fwo Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:76221 Serial 3725  
Permanent link to this record
 

 
Author Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A. url  doi
openurl 
  Title Size effects and strain state of Ga1-xInxAs/GaAs multiple quantum wells: Monte Carlo study Type A1 Journal article
  Year 2008 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 78 Issue 16 Pages 165326,1-165326,7  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The effect of the size of the GaAs barrier and the Ga1−xInxAs well on the structural properties of a Ga1−xInxAs/GaAs multiple quantum well structure is investigated using the Metropolis Monte Carlo approach based on a well-parametrized Tersoff potential. It is found that within the well the Ga-As and In-As bond lengths undergo contractions whose magnitude increases with increasing In content in sharp contrast with bond-length variations in the bulk Ga1−xInxAs systems. For fixed barrier size and In content, the contraction of the bonds is also found to increase with increasing size of the well. Using the local atomic structure of the heterostructures, a more local analysis of the strain state of the systems is given and comparison with the prediction of macroscopic continuum elasticity theory shows deviations from the latter.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000260574500084 Publication Date 2008-10-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 5 Open Access  
  Notes Approved Most recent IF: 3.836; 2008 IF: 3.322  
  Call Number UA @ lucian @ c:irua:72920 Serial 3036  
Permanent link to this record
 

 
Author Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. url  doi
openurl 
  Title Superconducting nanofilms: Andreev-type states induced by quantum confinement Type A1 Journal article
  Year 2008 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 78 Issue 5 Pages 054505,1-054505,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT)  
  Abstract Quantum confinement of the transverse electron motion is the major effect governing the superconducting properties of high-quality metallic nanofilms, leading to a nonuniform transverse distribution of the superconducting condensate. In this case the order parameter can exhibit significant local enhancements due to these quantum-size effects and, consequently, quasiparticles have lower energies when they avoid the local enhancements of the pair condensate. Such excitations can be considered as new Andreev-type quasiparticles but now induced by quantum confinement. By numerically solving the Bogoliubovde Gennes equations and using Anderson's approximate solution to these equations, we: (a) formulate a criterion for such new Andreev-type states (NATS) and (b) study their effect on the superconducting characteristics in metallic nanofilms. We also argue that nanofilms made of low-carrier-density materials, e.g., of superconducting semiconductors, can be a more optimal choice for the observations of NATS and other quantum-size superconducting effects.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000259368200109 Publication Date 2008-08-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 14 Open Access  
  Notes Approved Most recent IF: 3.836; 2008 IF: 3.322  
  Call Number UA @ lucian @ c:irua:76526 Serial 3356  
Permanent link to this record
 

 
Author Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. url  doi
openurl 
  Title Dependence of superconducting properties on the size and shape of a nanoscale superconductor: from nanowire to film Type A1 Journal article
  Year 2007 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 76 Issue Pages 024511,1-6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000248496200104 Publication Date 2007-07-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 54 Open Access  
  Notes Fwo-Vi; Iap; Bof-Top Approved Most recent IF: 3.836; 2007 IF: 3.172  
  Call Number UA @ lucian @ c:irua:69655 Serial 643  
Permanent link to this record
 

 
Author Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. url  doi
openurl 
  Title Oscillations of the superconducting temperature induced by quantum well states in thin metallic films: numerical solution of the Bogoliubov-de Gennes equations Type A1 Journal article
  Year 2007 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 75 Issue 1 Pages 014519,1-9  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000243894600126 Publication Date 2007-01-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 85 Open Access  
  Notes Fwo-Vi; Bof-Top; Iap Approved Most recent IF: 3.836; 2007 IF: 3.172  
  Call Number UA @ lucian @ c:irua:63749 Serial 2535  
Permanent link to this record
 

 
Author Shanenko, A.A.; Croitoru, M.D.; Zgirski, M.; Peeters, F.M.; Arutyunov, K. url  doi
openurl 
  Title Size-dependent enhancement of superconductivity in Al and Sn nanowires: shape-resonance effect Type A1 Journal article
  Year 2006 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 74 Issue 5 Pages 052502,1-4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000240238400015 Publication Date 2007-02-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 95 Open Access  
  Notes Approved Most recent IF: 3.836; 2006 IF: 3.107  
  Call Number UA @ lucian @ c:irua:60806 Serial 3034  
Permanent link to this record
 

 
Author Verbeeck, J.; Lebedev, O.I.; Van Tendeloo, G.; Mercey, B. url  doi
openurl 
  Title SrTiO3(100)/(LaMnO3)m(SrMnO3)n layered heterostructures: a combined EELS and TEM study Type A1 Journal article
  Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 66 Issue 18 Pages 184426  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Epitaxially grown heterostructures consisting of alternating layers of LaMnO(3) (LMO, 9 or 15 unit cells) and SrMnO(3) (SMO, 4 or 6 unit cells) on a SrTiO(3)(100) (STO(100)) substrate have been studied by a combination of high resolution transmission electron microscopy (HRTEM), electron diffraction, quantitative electron energy loss spectroscopy (EELS) with model fitting, energy filtered TEM (EFTEM) and imaging spectroscopy on an atomic scale. The combination of these techniques is necessary for the structural, chemical, and electronic characterization of these heterostructures. A model is proposed containing chemically and structurally sharp interfaces. The SrMnO(3) layers are stabilized in a Pm3m structure between two LMO layers. Tensile stress causes oxygen deficiency in the SMO layers increasing the number of 3d electrons on the Mn sites to resemble the Mn(3+) sites in LMO. The energy loss near edge structure (ELNES) of O and Mn is compared for both LMO and SMO layers and shows that the Mn-O bonds have a partially covalent character. The absence of a strong valency effect in the Mn ELNES is due to the oxygen vacancies in SMO.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000179633100062 Publication Date 2002-11-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 32 Open Access  
  Notes Approved Most recent IF: 3.836; 2002 IF: NA  
  Call Number UA @ lucian @ c:irua:54741 Serial 3563  
Permanent link to this record
 

 
Author Wang, Z.-H.; Kronmüller, H.; Lebedev, O.I.; Gross, G.M.; Razavi, F.S.; Habermeier, H.U.; Shen, B.G. url  doi
openurl 
  Title Phase transition and magnetic anisotropy of (La,Sr)MnO3 thin films Type A1 Journal article
  Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 65 Issue 5 Pages 054411-54416  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The magnetic proper-ties and their correlation with the microstructure and electrical transport are investigated in La0.88Sr0.1MnO3 films grown on (100)SrTiO3 Single crystal substrates with thickness ranging from 100 to 2500 Angstrom. The ultrathin film (t = 100 Angstrom) has a single ferromagnetic transition (FMT) at T-c of 250 K, whereas the thicker films exhibit two FMTs, with the main one at a lowered T-c of 200 K while the minor one around 300 K. Furthermore, a thickness dependent magnetic anisotropy has been found, strongly indicating the existence of strain effect, which is also revealed by the transmission electron microscopy study. The suppressed Jahn-Teller distortion (JTD) by the epitaxial strain, and the recovered JTD due to the strain relexation are suggested to explain the metallic behavior in thin films and the insulating behavior in the thick film (t = 2500 Angstrom), repectively.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000173647000058 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 23 Open Access  
  Notes Approved Most recent IF: 3.836; 2002 IF: NA  
  Call Number UA @ lucian @ c:irua:103883 Serial 2592  
Permanent link to this record
 

 
Author Mishra, R.S.K.; Pandey, D.; Lemmens, H.; Van Tendeloo, G. url  doi
openurl 
  Title Evidence for another low-temperature phase transition in tetragonal Pb(ZrxTi1-x)O3 (x=0.515,0.520) Type A1 Journal article
  Year 2001 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 64 Issue 5 Pages 054104  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Results of dielectric and resonance frequency (f(r)) measurements below room temperature are presented for Pb(ZrxTi1-x)O-3, x = 0.515 and 0.520. It is shown that the temperature coefficient of f(r) changes sign from negative to positive around 210 and 265 K for x = 0.520 and 200 and 260 K for x = 0.515. Anomalies in the real part of the dielectric constant (epsilon') are observed around the same temperatures at which the temperature coefficient of f(r) changes sign because of the electrostrictive coupling between the elastic and dielectric responses. Low-temperature powder x-ray-diffraction (XRD) data, however, reveal only one transition from the tetragonal to monoclinic phase similar to that reported by Noheda et al. [Phys. Rev. B, 61, 8687 (2000)]. Electron-diffraction data, on the other hand, reveal yet another structural transition at lower temperatures corresponding to the second anomaly in the epsilon' vs T and f(r) vs T curves. This second transition is shown to be a cell-doubling transition not observed by Noheda et al. in their XRD studies. The observation of superlattice reflections raises doubts about the correctness of the Cm space group proposed by Noheda et al. for the monoclinic phase of Pb(ZrxTi(1-x))O-3 below the second transition temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000170267000028 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited Open Access  
  Notes Approved Most recent IF: 3.836; 2001 IF: NA  
  Call Number UA @ lucian @ c:irua:103407 Serial 1093  
Permanent link to this record
 

 
Author Fedina, L.; Lebedev, O.I.; Van Tendeloo, G.; van Landuyt, J.; Mironov, O.A.; Parker, E.H.C. url  doi
openurl 
  Title In situ HREM irradiation study of point-defect clustering in MBE-grown strained Si1-xGex/(001)Si structures Type A1 Journal article
  Year 2000 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 61 Issue 15 Pages 10336-10345  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We present a detailed analysis of the point-defect clustering in strained Si/Si(1-x)Ge(x)/(001)Si structures, including the interaction of the point defects with the strained interfaces and the sample surface during 400 kV electron irradiation at room temperature. Point-defect cluster formation is very sensitive to the type and magnitude of the strain in the Si and Si(1-x)Ge(x) layers. A small compressive strain (-0.3%) in the SiGe alloy causes an aggregation of vacancies in the form of metastable [110]-oriented chains. They are located on {113} planes and further recombine with interstitials. Tensile strain in the Si layer causes an aggregation of interstitial atoms in the forms of additional [110] rows which are inserted on {113} planes with [001]-split configurations. The chainlike configurations are characterized by a large outward lattice relaxation for interstitial rows (0.13 +/-0.01 nm) and a very small inward relaxation for vacancy chains (0.02+/-0.01 nm). A compressive strain higher than -0.5% strongly decreases point-defect generation inside the strained SiGe alloy due to the large positive value of the formation volume of a Frenkel pair. This leads to the suppression of point-defect clustering in a strained SiGe alloy so that SiGe relaxes via a diffusion of vacancies from the Si layer, giving rise to an intermixing at the Si/SiGe interface. In material with a 0.9% misfit a strongly increased flow of vacancies from the Si layer to the SiGe layer and an increased biaxial strain in SiGe bath promote the preferential aggregation of vacancies in the (001) plane, which relaxes to form intrinsic 60 degrees dislocation loops.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000086606200082 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 27 Open Access  
  Notes Conference Name: Microsc. Semicond. Mater. Conf. Approved Most recent IF: 3.836; 2000 IF: NA  
  Call Number UA @ lucian @ c:irua:103456 Serial 1577  
Permanent link to this record
 

 
Author Maignan, A.; Martin, C.; Van Tendeloo, G.; Hervieu, M.; Raveau, B. url  doi
openurl 
  Title Size mismatch : a crucial factor for generating a spin-glass insulator in manganites Type A1 Journal article
  Year 1999 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 60 Issue 22 Pages 15214-15219  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Thr structural, electronic, and magnetic properties of the highly mismatched perovskite oxides, Th(0.35)A(0.65)MnO(3), where Ais for the alkaline earth divalent cations (Ca, Ba, Sr), which are all characterized by the same large tolerance factor (t=0.934), have been investigated by using electron microscopy, electrical resistivity, magnetic susceptibility, and magnetization. It is clearly established that a transition from ferromagnetic metallic towards spin-glass insulator samples is induced as the A-site cationic size mismatch is increased. Moreover, the magnetoresistance (MR) properties of these manganites are strongly reduced for the spin-glass insulators, demonstrating that the A-sire cationic disorder is detrimental for the colossal MR properties. Based on these results, a new electronic and magnetic diagram is established that shows that the A-site disorder, rather than the A-site average cationic size (or t) is the relevant factor for generating spin-glass insulating manganites. [S0163-1829(99)01746-4].  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000084631600039 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 75 Open Access  
  Notes Approved Most recent IF: 3.836; 1999 IF: NA  
  Call Number UA @ lucian @ c:irua:104280 Serial 3038  
Permanent link to this record
 

 
Author De Meulenaere, P.; Rodewald, M.; Van Tendeloo, G. url  doi
openurl 
  Title Anisotropic cluster model for the short-range order in Cu1-xPdx-type alloys Type A1 Journal article
  Year 1998 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 57 Issue 18 Pages 11132-11140  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The split diffuse maxima around the {110} and {100} positions in the diffraction pattern of short-range-ordered Cu1-xPdx alloys (x=0.10...0.60) are attributed to small atomic clusters, being part of the underlying fee lattice. By analyzing the reciprocal space geometry, our cluster method identifies two prominent cluster types: the tetrahedron of nearest neighbors and a linear three-points cluster along the [110] directions. Since both cluster types contain different information on the same nearest-neighbor correlations, local anisotropy has to be assumed. It is shown that the three interatomic pair interactions within these basic clusters are sufficient to generate the spot splitting in the diffraction pattern. A ground-state analysis with these interactions reproduces the results of the anisotropic next-nearest-neighbor Ising model.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000073585200026 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 1 Open Access  
  Notes Approved Most recent IF: 3.836; 1998 IF: NA  
  Call Number UA @ lucian @ c:irua:25678 Serial 125  
Permanent link to this record
 

 
Author Rodewald, M.; Rodewald, K.; De Meulenaere, P.; Van Tendeloo, G. url  doi
openurl 
  Title Real-space characterization of short-range order in Cu-Pd alloys Type A1 Journal article
  Year 1997 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 55 Issue 21 Pages 14173-14181  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Cu-Pd alloys containing 10, 20, 30, 40, and 50 at. % Pd and quenched from a temperature just above the ordering temperature T-c are investigated by electron diffraction and high-resolution electron microscopy (HREM). The results show diffuse electron diffraction intensities at {100} and {110} positions for the alloy with 10 at. % Pd, but with a characteristic twofold and fourfold splitting for the alloys with more than 10 at. % Pd. High-resolution images show the formation of microdomains best developed between 20 and 30 at. % Pd. A real-space characterization has been performed by applying videographic real-structure simulations revealing that the splitting of the diffuse maxima depends on the average distance between microdomains of Cu3Au type in antiphase with each other. By applying image processing routines on the HREM images, correlation vectors are identified which correspond to correlations between microdomains.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos A1997XE37100036 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 15 Open Access  
  Notes Approved Most recent IF: 3.836; 1997 IF: NA  
  Call Number UA @ lucian @ c:irua:21439 Serial 2828  
Permanent link to this record
 

 
Author Gensterblum, G.; Hevesi, K.; Han, B.Y.; Yu, L.M.; Pireaux, J.J.; Thiry, P.A.; Caudano, R.; Lucas, A.A.; Bernaerts, D.; Amelinckx, S.; Van Tendeloo, G.; Bendele, G.; Buslaps, T.; Johnson, R.L.; Foss, M.; Feidenhans’l, R.; Le Lay, G.; url  doi
openurl 
  Title Growth mode and electronic-structure of the epitaxial C60(111)/GeS(001) interface Type A1 Journal article
  Year 1994 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 50 Issue 16 Pages 11981-11995  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos A1994PR43400080 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.736 Times cited 81 Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:99825 Serial 1393  
Permanent link to this record
 

 
Author Linard, F.J.A.; Moura, V.N.; Covaci, L.; Milošević, M.V.; Chaves, A. url  doi
openurl 
  Title Wave-packet scattering at a normal-superconductor interface in two-dimensional materials : a generalized theoretical approach Type A1 Journal article
  Year 2023 Publication Physical review B Abbreviated Journal  
  Volume 107 Issue 16 Pages 165306-165309  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract A wave-packet time evolution method, based on the split-operator technique, is developed to investigate the scattering of quasiparticles at a normal-superconductor interface of arbitrary profile and shape. As a practical application, we consider a system where low-energy electrons can be described as Dirac particles, which is the case for most two-dimensional materials, such as graphene and transition-metal dichalcogenides. However, the method is easily adapted for other cases such as electrons in few-layer black phosphorus or any Schrodinger quasiparticles within the effective mass approximation in semiconductors. We employ the method to revisit Andreev reflection in mono-, bi-, and trilayer graphene, where specular-and retro-reflection cases are observed for electrons scattered by a steplike superconducting region. The effect of opening a zero-gap channel across the superconducting region on the electron and hole scattering is also addressed, as an example of the versatility of the technique proposed here.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000974675700006 Publication Date 2023-04-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.7 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.7; 2023 IF: 3.836  
  Call Number UA @ admin @ c:irua:196709 Serial 8954  
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